Teaching Case

A 54-year-old female presented to the Emergency Department for weakness, epigastric discomfort and nausea.

Her past clinical history included Hodgkin lymphoma in remission since 2018, polycystic liver and kidney disease and hypertension. She referred that five days before she had stopped the diuretic because of low blood pressure.

A chest CT scan was performed to rule out pulmonary embolism because of the arterial blood gas analysis results; it revealed a 6 cm mass occupying the right atrium (RA) (Fig.1).

Echocardiography was then performed, in the hypothesis of atrial myxoma. It confirmed the presence of a mass that was not attached to the interatrial septum and that was occupying nearly the entire RA. The superior vena cava was dilated and the flow in the inferior vena cava (IVC) wasn’t detected at colour-doppler.

A multiphase CT scan of the abdomen was performed in the hypothesis of tumour thrombus. It showed a 10 cm mass in the VII-VIII hepatic segment with inhomogeneous contrast enhancement in the arterial phase (Fig.2-3) and portal venous phase washout (Fig.4) with tumour thrombus extending from the hepatic veins into the IVC and RA; it also revealed thrombosis of the IVC that reached the iliac bifurcation (Fig.5).

Liver cancer is the seventh most common malignancy in the world and the second most common cause of cancer death [1]. Hepatocellular carcinoma (HCC) is the main type of liver cancer and accounts for approximately 75% of cases [2]. Cirrhosis from any aetiology is the main risk factor for HCC. Other risk factors are HBV, HCV, chronic alcohol consumption, diabetes, obesity and non-alcoholic fatty liver disease (NAFLD) [3].

HCC has a propensity for intravascular spread and tends to infiltrate the portal vein and its branches, and more rarely, the hepatic veins. Extension  in the hepatic veins and IVC can result in tumour growth into the RA. The incidence of cardiac involvement in HCC ranges from 1.2 to 4% [4].

In our case, the accidental finding of a large intracardiac mass was at first interpreted as a primary cardiac tumour. Further imaging showed the occlusion of the IVC and a large hepatic mass unevenly hyperdense in the arterial phase and hypodense in the portal phase suggestive of HCC.  

The diagnosis of HCC can be established by contrast-enhanced imaging findings in cirrhotic patient according to EASL guidelines [5] or applying LI-RADS criteria in high-risk patients (patient with cirrhosis, chronic HBV and current or prior HCC). The classification LR-TIV (LI-RADS tumour in vein) should be applied when there is unequivocally enhancing soft tissue within a vein, regardless of visualization of parenchymal mass. HCC with portal vein invasion often lack arterial hypervascularity because of compensatory increased arterial supply to the background liver [6].

Alpha-fetoprotein (AFP) >400–500 ng/ml is considered diagnostic for HCC (specificity close to 100%, sensitivity 20-45%) [7]. In addition, AFP-L3 levels have been associated with portal vein invasion [5].

In our case histological analysis was mandatory so an ultrasound-guided biopsy which confirmed HCC was performed.

Tumour thrombus in the IVC and RA has been associated with limited treatment options. There may be a modest benefit with radiation, palliative surgery, chemoembolization, or systemic treatment [8]: a recent trial showed significantly better overall survival and progression­ free survival outcomes with atezolizumab plus bevacizumab than with sorafenib in patients with unresect­able HCC [9]. Our patient received palliative and supportive care because in the following weeks she developed obstructive cardiogenic shock and multi-organ failure.

In conclusion, this is a unique case of HCC with tumour thrombus in IVC and right atrium in a patient without signs of heart failure or hemodynamic instability at presentation and without evidence of cirrhosis, viral hepatitis or other risk factors.

Written informed patient consent for publication has been obtained.